Trouble is for Leo himself. Come the world cup he will need to win games like the one against Romania on his own and as well as he played they didn't win and all the media and many worldwide see is Leo as a goal scorer.
Argentina could make his job easier by playing well, but failing that the whole worlds media and many fans expects Messi to win every game by himself even if Argentina are weak. In order for him to challenge for a world cup and become best ever in many's eyes.
If that was a World Cup Game, the world wouldn't say Argentina were poor but Messi played well. They would only say "Messi fails again to perform for Argentina".
The crazy fact is, Messi has to make Argentina win every game otherwise people will abuse him and that is a ridiculous amount of Pressure for him to be under. Maybe that is the reason he is seeming a bit stressed and not at his free flowing best.
Leo is in a no win situation unless he wins the World Cup and scores at least 6. which is virtually impossible.